Many countries have an emergency response phone number that users can call to connect the caller to a call center, such as a public safety answering point (PSAP) call center of a government agency, which has jurisdiction over an area from which the caller is calling. The call center receives the call and can, in some cases, dispatch appropriate resources, such as firefighters, police, or ambulance first responders.
Many emergency response systems use enhanced emergency calling systems (e.g., e911 in North America) or similar technology to identify a phone number from which an emergency call was made and an address or location corresponding to that phone number. Such systems generally include a database, such as a private switch/automatic location information database that allows the PSAP to look up the caller's address associated with the phone number from which the call is made. These systems work relatively well when the database has accurate location information for a given phone number. However, when several phone numbers are associated with a particular building or area, such as the case of private branch exchange (PBX) systems, any location information stored in a database may not provide accurate location information for the caller.
PBX users are typically grouped into logical zones—e.g., by floor, by wing, by department, or the like. Each of these groupings is known as Emergency Response Location (ERL). Depending on the system, each ERL is typically assigned an emergency location identification number (ELIN) or a customer emergency service identification (CESID). Using ELIN or CESID information to identify a group of users reduces a number of records stored in the PS-ALI database. Thus, costs of the system can be reduced, and setup and maintenance of the e911 database can be simplified. When a call is made from a PBX extension to an emergency number (e.g., 911), a pre-assigned DID number based on the calling extension's ERL and matching ELIN will be sent to the call center to facilitate identifying a location of the caller.
Several challenges to providing accurate location information for a caller over a multi-line telephone system (MLTS), such as a PBX, exist. For example, significant overhead is required to map PBX extensions to physical locations within the property and to enter and maintain this information in an appropriate database. In addition, various communication systems allow for the use of call groups, wherein multiple devices can use a single number, making location information of a particular device difficult to determine. For example, if a device within the call or ring group is mobile and is using a VoIP application (e.g., a tablet computer such as an iPad or iPod), more complexities arise, because an emergency call placed from such a device will appear to originate from a wired phone, such as a user's desk phone, and not from the mobile device. Such problems can be particularly problematic for organizations, such as hospitality services providers, universities, schools, hospitals, and the like, where liabilities can be introduced when the incorrect location of a guest is reported during an emergency response. This emergency calling issue often prevents such organizations from offering voice services for fear of the potential liabilities.
Emergency calls can also be made from mobile phones. In the case of e911 and similar services, when an emergency call is originated from a mobile phone or similar device, nearest cell tower information and GPS location information can be sent to a call center to help identify a location of the caller. However, such information may not be as accurate as desired, particularly in large buildings, because GPS information can be inaccurate for indoor locations (e.g., it may be difficult to determine from which floor a user is calling). Moreover, GPS-based location devices within mobile devices may not function in some buildings due to poor GPS signal penetration.
Other problems can arise when mobile devices use WiFi or other wireless (e.g., digital enhanced cordless telecommunications (DECT)) technology. Some WiFi and DECT access points have been designed to provide location information that can be leveraged in emergency scenarios. However, the coverage area for these wireless technologies can be quite large, and connectivity to an access point on a floor above or below the user are commonplace. Thus, incorrect location information associated with a caller can result. Further, if a mobile device user uses a cellular connection, rather than a wireless technology connection, the user will not gain the benefit of the wireless or WiFi location ability to provide location information.
In addition, teleworker functionality, which allows remote users access through a firewall to a PBX, may result in providing incorrect location information for an e911 caller. For example, a teleworker system may indicate that a caller is at his or her desk, when he or she is instead away from the office.
Accordingly, improved systems and methods for providing accurate location of an emergency number caller are desired. The improved systems and methods may desirably leverage existing databases and systems. The improved systems and methods may additionally or alternatively provide relatively accurate location information for callers using a mobile device when, for example, inside a building, such as a building using a PBX.
It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of illustrated embodiments of the present disclosure.